Installation guide
Once the boot loader screen has returned, type b to boot the system.
Once you have booted into single user mode and have access to the # prompt, you must type
passwd root, which allows you to enter a new password for root. At this point you can type
shutdown -r now to reboot the system with the new root password.
If you cannot remember your user account password, you must become root. To become root, type
su - and enter your root password when prompted. Then, type passwd <username>. This allows
you to enter a new password for the specified user account.
If the graphical login screen does not appear, check your hardware for compatibility issues. The
Hardware Compatibility List can be found at:
http://hardware.redhat.com/hcl/
6.4 .6. Is Your RAM Not Being Recognized?
Sometimes, the kernel does not recognize all of your memory (RAM). You can check this with the cat
/proc/meminfo command.
Verify that the displayed quantity is the same as the known amount of RAM in your system. If they are
not equal, add the following line to the /boot/grub/grub.conf:
mem=xxM
Replace xx with the amount of RAM you have in megabytes.
In /boot/grub/grub.conf, the above example would look similar to the following:
# NOTICE: You have a /boot partition. This means that
# all kernel paths are relative to /boot/
default=0
timeout=30
splashimage=(hd0,0)/grub/splash.xpm.gz
title Red Hat Enterprise Linux (2.6.9-5.EL)
root (hd0,0)
kernel /vmlinuz-2.6.9-5.EL ro root=/dev/hda3 mem=128M
Once you reboot, the changes made to grub.conf are reflected on your system.
Once you have loaded the GRUB boot screen, type e for edit. You are presented with a list of items in
the configuration file for the boot label you have selected.
Choose the line that starts with kernel and type e to edit this boot entry.
At the end of the kernel line, add
mem=xxM
where xx equals the amount of RAM in your system.
Press Enter to exit edit mode.
Once the boot loader screen has returned, type b to boot the system.
Itanium users must enter boot commands with elilo followed by the boot command.
Red Hat Ent erprise Linux 5 Inst allat ion G uide
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